Abstract

Purpose of Review

Intervertebral discs (IVD) are derived from embryonic notochord and sclerotome. The nucleus pulposus is derived from notochord while other connective tissues of the spine are derived from sclerotome. This manuscript will review the past 5 years of research into IVD development.

Recent Findings

Over the past several years, advances in understanding the step-wise process that govern development of the nucleus pulposus and the annulus fibrosus have been made. Generation of tissues from induced or embryonic stem cells into nucleus pulposus and paraxial mesoderm derived tissues has been accomplished in vitro using pathways identified in normal development. A balance between BMP and TGF-ß signaling as well as transcription factors including Pax1/Pax9, Mkx, and Nkx3.2 appear to be very important for cell fate decisions generating tissues of the IVD.

Summary

Understanding how the IVD develops will provide the foundation for future repair, regeneration, and tissue engineering strategies for IVD disease.

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